Possible fix for binoc perma zoom (#4176)

# About the pull request

I have no consistent reproducibility for this but this may fix it? Seems
to occur when an explosion blows up the binocs in the hand of the person
while zoomed.


# Explain why it's good for the game

Bug bad

# Testing Photographs and Procedure
<details>
<summary>Screenshots & Videos</summary>

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screenshots and the `<details>` tags.

</details>


# Changelog

:cl: Morrow
fix: Possible fix for binoc perma zoom
/:cl:

code/game/objects/items.dm

@@ -829,6 +829,7 @@ cases. Override_icon_state should be a list.*/
 	UnregisterSignal(src, list(
 		COMSIG_ITEM_DROPPED,
 		COMSIG_ITEM_UNWIELD,
+		COMSIG_PARENT_QDELETING,
 	))
 	UnregisterSignal(user, COMSIG_MOB_MOVE_OR_LOOK)
 	//General reset in case anything goes wrong, the view will always reset to default unless zooming in.
@@ -861,6 +862,7 @@ cases. Override_icon_state should be a list.*/
 		RegisterSignal(src, list(
 			COMSIG_ITEM_DROPPED,
 			COMSIG_ITEM_UNWIELD,
+			COMSIG_PARENT_QDELETING,
 		), PROC_REF(unzoom_dropped_callback))
 		RegisterSignal(user, COMSIG_MOB_MOVE_OR_LOOK, PROC_REF(zoom_handle_mob_move_or_look))